The Atlantic's Warm Streak

As autumn sets in, North Americans can usually expect brisk morning temperatures in September and October. But just because the air gets a little crisper doesn't mean that the oceans have cooled down.

In fact, this autumn temperatures in the Atlantic Ocean temperatures look to stay quite warm for a while, which means that it could produce hurricanes well into November. In this image, blue indicates cool ocean temperatures and orange indicates waters warm enough to fuel hurricanes.

The warm ocean water that fuels hurricanes can come from as far away as Africa. A "seed storm" brews up off the west coast of Africa and follows an easterly course across the Atlantic, picking up steam as it goes. As hurricanes evaporate warm surface waters, cooler water from deeper in the ocean rises to replace it.

As long as the storm keeps moving it can continue to grow off warm water - but if it stalls over cool water it can lose some of its strength.

However, once a storm enters the Gulf of Mexico, where waters are shallower and warmer than in the Atlantic, storms can grow much more intense because of the large supply of warm water.

As hurricanes suck up warm water they leave a trail of cold water behind them. In this image there is still a hint of cold water east of the Carolinas where Hurricane Ophelia recently passed.

--Bjorn Carey

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Credit: NASA Earth Observatory